116 resultados para characteristic class
Resumo:
Introduction: The objectives of this investigation were to compare the initial cephalometric characteristics of complete Class II Division 1 malocclusions treated with 2 or 4 premolar extractions and to verify their influence on the occlusal success rate of these treatment protocols. Methods: A sample of 98 records from patients with complete Class II Division 1 malocclusion was divided into 2 groups with the following characteristics: group 1 consisted of 55 patients treated with 2 maxillary first premolar extractions at an initial mean age of 13.07 years; group 2 included 43 patients treated with 4 premolar extractions, with an initial mean age of 12.92 years. Initial and final occlusal statuses were evaluated on dental casts with Grainger`s treatment priority index (TPI), and the initial cephalometric characteristics were obtained from the pretreatment cephalograms. The initial cephalometric characteristics and the initial and final occlusal statuses of the groups were compared with the t test. A multiple regression analysis was used to evaluate the influence of all variables in the final TPI. Results: The 2-premolar extraction protocol provided a statistically smaller TPI and consequently a better occlusal success rate than the 4-premolar extraction protocol. The 4-premolar extraction group had statistically smaller apical base lengths, more vertical facial growth patterns, and greater hard- and soft-tissue convexities at pretreatment than the 2-premolar extraction group. However, the multiple regression analysis showed that only the extraction protocol was significantly associated with the final occlusal status. Conclusions: The initial cephalometric characteristics of the groups did not influence the occlusal success rate of these 2 treatment protocols.
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Purpose: The aim of this study was to assess the 6-year performance of the ART (atraumatic restorative treatment) approach in Class III restorations in permanent teeth. Materials and Methods: A total of 127 ART Class III restorations, using Ketac-Molar (3M ESPE) ionomer cement, was performed in 58 adult patients by one experienced operator in 1998. After a 6 years, 34 patients and 65 restorations were evaluated according to ART criteria. Two calibrated examiners carried out the evaluation. Data were analyzed by exact 95% Confidence Interval and Survival Analysis using the Jackknife method for standard error determination. Results: Among assessed restorations, 73.8% (95% CI = 61.5% to 86.2%) were in good condition and classified as successful, with a 67.6% (95% CI = 54.4% to 80.7%) cumulative survival rate. Failed restorations included 13.9% completely or partially missing restorations, 9.2% restorations that had been replaced by other treatment, 1.5% restorations with a large defect at the margin, and 1.5% restorations that presented high wear on the surface. No caries was observed even in those teeth in which restorations were absent. Conclusion: The 6-year success rate of the ART approach in anterior permanent teeth (Class III) was considered high.
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Introduction: The purpose of this study was to compare the occlusal outcomes and the efficiency of 1-phase and 2-phase treatment protocols in Class II Division 1 malocclusions. Treatment efficiency was defined as a change in the occlusal characteristics in a shorter treatment time. Methods: Class II Division 1 subjects ( n = 139) were divided into 2 groups according to the treatment protocol for Class II correction. Group 1 comprised 78 patients treated with a 1-phase treatment protocol at initial and final mean ages of 12.51 and 14.68 years. Group 2 comprised 61 patients treated with a 2-phase treatment protocol at initial and final mean ages of 11.21 and 14.70 years. Lateral cephalometric radiographs were taken at the pretreatment stage to evaluate morphological differences in the groups. The initial and final study models of the patients were evaluated by using the peer assessment rating index. Chi-square tests were used to test for differences between the 2 groups for categorical variables. Variables regarding occlusal results were compared by using independent t tests. A linear regression analysis was completed, with total treatment time as the dependent variable, to identify clinical factors that predict treatment length for patients with Class II malocclusions. Results: Similar occlusal outcomes were obtained between the 1-phase and the 2-phase treatment protocols, but the duration of treatment was significantly shorter in the 1-phase treatment protocol group. Conclusions: Treatment of Class II Division 1 malocclusions is more efficient with the 1-phase than the 2-phase treatment protocol.
Resumo:
Correcting a Class III subdivision malocclusion is usually a challenge for an orthodontist, especially if the patient`s profile does not allow for any extractions. One treatment option is to use asymmetric intermaxillary elastics to correct the unilateral anteroposterior discrepancy. However, the success of this method depends on the individual response of each patient and his or her compliance in using the elastics. The objectives of this article were to present a successful treatment of a Class III subdivision patient with this approach and to illustrate and discuss the dentoskeletal changes that contributed to the correction. (Am J Orthod Dentofacial Orthop 2010;138:221-30)
A modified orthodontic protocol for advanced periodontal disease in Class II division 1 malocclusion
Resumo:
An interdisciplinary approach is often the best option for achieving a predictable outcome for an adult patient with complex clinical problems. This case report demonstrates the combined periodontal/orthodontic treatment for a 49-year-old woman presenting with a Class II Division 1 malocclusion with moderate maxillary anterior crowding, a 9-mm overjet, and moderate to severe bone loss as the main characteristics of the periodontal disease. The orthodontic treatment included 2 maxillary first premolar extractions through forced extrusion. Active orthodontic treatment was completed in 30 months. The treatment outcomes, including the periodontal condition, were stable 17 months after active orthodontic treatment. The advantages of this interdisciplinary approach are discussed. Periodontally compromised orthodontic patients can be satisfactorily treated, achieving most of the conventional orthodontic goals, if a combined orthodontic/periodontic approach is used. (Am J Orthod Dentofacial Orthop 2011; 139:S133-44)
Resumo:
The present study aimed to evaluate the cephalometric changes in Class II patients treated exclusively with cervical headgear (CHG) in the maxillary arch and fixed appliances in the mandibular arch as compared with a control group. The sample comprised 82 lateral cephalograms obtained pre- (T1) and post- (T2) treatment/observation of 41 subjects, divided into two groups: group 1-25 Class II division 1 patients (20 females and five males), with a mean pre-treatment age of 10.4 years, treated for a mean period of 2.5 years and group 2-16 Class II untreated subjects (12 females and four males), with a mean initial age of 9.9 years, followed for a mean period of 2.2 years. Treatment changes between the groups were compared by means of t-tests. The results showed restriction of maxillary forward displacement and also a restriction in maxillary length growth, improvement in the maxillomandibular relationship, restriction of mandibular incisor vertical development, reduction in overjet and overbite, and improvement in molar relationship. It was concluded that this treatment protocol corrected the Class II malocclusion characteristics primarily through maxillary forward growth restriction.
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A clinical Klebsiella pneumoniae isolate carrying the extended-spectrum beta-lactamase gene variants bla(SHV-40), bla(TEM-116) and bla(GES-7) was recovered. Cefoxitin and ceftazidime activity was most affected by the presence of these genes and an additional resistance to trimethoprim-sulphamethoxazole was observed. The bla(GES-7) gene was found to be inserted into a class 1 integron. These results show the emergence of novel bla(TEM) and bla(SHV) genes in Brazil. Moreover, the presence of class 1 integrons suggests a great potential for dissemination of bla(GES) genes into diverse nosocomial pathogens. Indeed, the bla(GES-7) gene was originally discovered in Enterobacter cloacae in Greece and, to our knowledge, has not been reported elsewhere.
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Supercritical carbon dioxide (SC-CO(2)) extractions of Brazilian cherry (Eugenia uniflora L.) were carried out under varied conditions of pressure and temperature, according to a central composite 2(2) experimental design, in order to produce flavour-rich extracts. The composition of the extracts was evaluated by gas chromatography coupled with mass spectrometry (GC/MS). The abundance of the extracted compounds was then related to sensory analysis results, assisted by principal component and factorial discriminant analysis (PCA and FDA, respectively). The identified sesquiterpenes and ketones were found to strongly contribute to the characteristic flavour of the Brazilian cherry. The extracts also contained a variety of other volatile compounds, and part of the fruit wax contained long-chain hydrocarbons that according to multivariate analysis, contributed to the yield of the extracts, but not the flavour. Volatile phenolic compounds, to which antioxidant properties are attributed, were also present in the extracts in high proportion, regardless of the extraction conditions. (C) 2010 Elsevier Ltd. All rights reserved.
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The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm(2)). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU) of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation immediately after irradiation, although this reduction was not observed 6 weeks after the baseline.
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A new piggyBac-related transposable element (TE) was found in the genome of a mutant Anticarsia gemmatalis multiple nucleopolyhedrovirus interrupting an inhibitor of apoptosis gene. This mutant virus induces apoptosis upon infection of an Anticarsia gemmatalis cell line, but not in a Trichoplusia ni cell line. The sequence of the new TE (which was named IDT for iap disruptor transposon) has 2531 bp with two DNA sequences flanking a putative Transposase (Tpase) ORF of 1719 bp coding for a protein with 572 amino acids. These structural features are similar to the piggyBac TE, also reported for the first time in the genome of a baculovirus. We have also isolated variants of this new TE from different lepidopteran insect cells and compared their Tpase sequences.
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An aspartic endopeptidase was purified in our laboratory from Rhipicephalus (Boophilus) microplus eggs [Logullo, C., Vaz, I.S., Sorgine, M.H., Paiva-Silva, G.O., Faria, F.S., Zingali, R.B., De Lima, M.F., Abreu, L., Oliveira, E.F., Alves, E.W, Masuda, H., Gonzales, J.C., Masuda, A., and Oliveira, P.L., 1998. Isolation of an aspartic proteinase precursor from the egg of a hard tick, Rhipicephalus (Boophilus) microplus. Parasitology 116, 525-532]. Boophilus yolk cathepsin (BYC) was tested as component of a protective vaccine against the tick, inducing a significant immune response in cattle [da Silva, VI., Jr., Logullo, C., Sorgine, M., Velloso, F.F., Rosa de Lima, M.F., Gonzales, J.C., Masuda, H., Oliveira, P.L., and Masuda, A., 1998. Immunization of bovines with an aspartic proteinase precursor isolated from Rhipicephalus (Boophilus) microplus eggs. Vet. Immunol. Immunopathol. 66,331-341]. In this work, BYC was cloned and its primary sequence showed high similarity with other aspartic endopeptidases. In spite of this similarity, BYC sequence shows many important differences in relation to other aspartic peptidases, the most important being the lack of the second catalytic Asp residue, considered to be essential for the catalysis of this class of endopeptidases. When we determined BYC cleavage specificity by LC-MS, we found out that it presents a preference for hydrophobic residues in P1 and P1` in accordance to most aspartic endopeptidases. Also, when analyzed by circular dicroism, BYC presented high beta sheet content, also a characteristic of aspartic endopeptidases. On the other hand, although both native and recombinant BYC are catalytically active, they present a very low specific activity, what seems to indicate that this peptidase will digest its natural substrate, vitellin, very slowly. We speculate that such a slow Vn degradative process might constitute an important strategy to preserve egg protein content to the hatching larvae. (c) 2007 Elsevier Inc. All rights reserved.
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This paper proves the multiplicity of positive solutions for the following class of quasilinear problems: {-epsilon(p)Delta(p)u+(lambda A(x) + 1)vertical bar u vertical bar(p-2)u = f(u), R(N) u(x)>0 in R(N), where Delta(p) is the p-Laplacian operator, N > p >= 2, lambda and epsilon are positive parameters, A is a nonnegative continuous function and f is a continuous function with subcritical growth. Here, we use variational methods to get multiplicity of positive solutions involving the Lusternick-Schnirelman category of intA(-1)(0) for all sufficiently large lambda and small epsilon.
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This paper proves the existence of nontrivial solution for a class of quasilinear systems oil bounded domains in R(N), N >= 2, whose nonlinearity has a double criticality. The proof is based oil a linking theorem without the Palais-Smale condition.
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A temporally global solution, if it exists, of a nonautonomous ordinary differential equation need not be periodic, almost periodic or almost automorphic when the forcing term is periodic, almost periodic or almost automorphic, respectively. An alternative class of functions extending periodic and almost periodic functions which has the property that a bounded temporally global solution solution of a nonautonomous ordinary differential equation belongs to this class when the forcing term does is introduced here. Specifically, the class of functions consists of uniformly continuous functions, defined on the real line and taking values in a Banach space, which have pre-compact ranges. Besides periodic and almost periodic functions, this class also includes many nonrecurrent functions. Assuming a hyperbolic structure for the unperturbed linear equation and certain properties for the linear and nonlinear parts, the existence of a special bounded entire solution, as well the existence of stable and unstable manifolds of this solution are established. Moreover, it is shown that this solution and these manifolds inherit the temporal behaviour of the vector field equation. In the stable case it is shown that this special solution is the pullback attractor of the system. A class of infinite dimensional examples involving a linear operator consisting of a time independent part which generates a C(0)-semigroup plus a small time dependent part is presented and applied to systems of coupled heat and beam equations. (C) 2010 Elsevier Ltd. All rights reserved.
Resumo:
In the analysis of stability of a variant of the Crank-Nicolson (C-N) method for the heat equation on a staggered grid a class of non-symmetric matrices appear that have an interesting property: their eigenvalues are all real and lie within the unit circle. In this note we shall show how this class of matrices is derived from the C-N method and prove that their eigenvalues are inside [-1, 1] for all values of m (the order of the matrix) and all values of a positive parameter a, the stability parameter sigma. As the order of the matrix is general, and the parameter sigma lies on the positive real line this class of matrices turns out to be quite general and could be of interest as a test set for eigenvalue solvers, especially as examples of very large matrices. (C) 2010 Elsevier B.V. All rights reserved.